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Home >> Mazda >> 2021 >> CX-3 FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Heated Oxygen Sensor (Ho2S) Removal/Installation
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Heated Oxygen Sensor (Ho2S) Removal/Installation

WARNING:
  • A hot engine and exhaust system can cause severe burns. Turn off the engine and wait until they are cool before removing the exhaust system.
CAUTION:
  • Do not allow flammable objects such as the taping for bundling wiring harness to come into contact with the exhaust manifold and silencer.
NOTE:
  • If penetrant lubricating spray penetrates the airflow hole of the HO2S, it could cause interference with the HO2S function.
  • When removing the HO2S, wrap a rag around the lower position so that penetrant lubricating spray does not get sprayed into the airflow hole.
G12726676Courtesy of MAZDA MOTORS CORP.
  1. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
  2. Lift up the vehicle.
  3. Remove the insulator. (See EXHAUST SYSTEM REMOVAL/INSTALLATION .)
  4. Disconnect the HO2S connector.
    G12726677Courtesy of MAZDA MOTORS CORP.
  5. Remove the clip from the body.
  6. Remove the HO2S using the SST.
    G12726678Courtesy of MAZDA MOTORS CORP.
  7. Install in the reverse order of removal.